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Investment Securities - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Security	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Securities available for sale	$ 1,020,986	$ 762,661
Other investments	44,700	25,200
Equity Securities, FV-NI	$ 6,200	1,200
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security	207
Equity Securities, FV-NI, Gain (Loss)	$ 0	0
Total debt securities, Amortized Cost	1,138,425	898,702
Debt Securities, Available-for-Sale	1,020,986	762,661
Obligations of U.S. Government-Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale	494,600
Total debt securities, Amortized Cost	559,800
Debt Securities, Available-for-Sale	494,600
Held-to-maturity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Deposit Liabilities, Collateral Issued, Financial Instruments	98,100	368,800
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Deposit Liabilities, Collateral Issued, Financial Instruments	386,500	626,700
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale	494,599	448,989
Total debt securities, Amortized Cost	559,769	527,777
Debt Securities, Available-for-Sale	494,599	448,989
Corporate Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale	48,412	29,204
Total debt securities, Amortized Cost	51,886	32,010
Debt Securities, Available-for-Sale	48,412	29,204
Sales [Member]
Debt Securities, Available-for-sale [Line Items]
Gross Gains	0	0	$ 0
Calls And Maturities [Member]
Debt Securities, Available-for-sale [Line Items]
Gross Gains	$ 0	$ 2	$ 16

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